The subject matter disclosed herein relates to power generating systems, and, more particularly, to power generating systems having synchronous generators with multiplex windings and multilevel inverters.
Ground vehicles, such as military vehicles, construction equipment, etc. have large electric drives that require advanced power systems to meet high power demands (e.g., >250 kW). To provide such high power levels, multilevel topologies have been considered to achieve low harmonic distortion with moderate switching frequency and reduced electromagnetic interference (“EMI”) emissions compared to a standard 2-level active rectifier-inverter system. Multilevel inverters function to synthesize a desired voltage from several levels of DC voltages (e.g., from multiple sources). A cascaded H-bridges inverter can be used to drive traction motors and other motor driven loads and requires multiple isolated DC power sources. Multiple isolated DC power sources can be achieved by generators with multi-channel configurations. One application of such multi-channel configurations is “duplex” or “multiplex” stator (armature) winding. Duplex stator winding configurations are typically used in induction machines. Induction machines with duplex stator windings include, but are not limited to, simple and cost-effective solutions for six-phase operation using two sets of three-phase subsystems, fault-tolerant applications, and/or reduction of cross section of magnet wire and terminal leads. Wound-field and permanent magnet (PM) brushless machines belong to the family of synchronous machines. Applications of duplex windings to synchronous machines may be associated with a risk of current unbalance and circulating currents. These effects can lead to immediate thermal damage of the stator winding insulation due to overheating. Thus, improved multiplex winding systems may be desirable.